French President Emmanuel Macron on Monday is set to address France for the first time since signing into law his controversial pension reform, facing warnings that the political and social crisis sparked by the changes is not over.

Macron signed the legislation early Saturday, just hours after the banner change to raise the retirement age from 62 to 64 had been validated by the constitutional court, prompting accusations he was smuggling the law through in the dead of night.

After three months of protests and strikes, the left and unions have warned of mass protests on Labour Day on May 1.

Polls have consistently shown that a majority of French remain opposed to the reform, which the government forced through parliament using a controversial mechanism allowing it to be passed without a vote.

Meanwhile, Macron's own personal popularity ratings have plunged, with some analysts suggesting that he has given a head-start to far-right leader Marine Le Pen in the long path to the 2027 elections.

The press has widely dubbed it a "Pyrrhic victory", in reference to the Greek king who defeated the Romans but saw most of his army destroyed in the process.

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'President of chaos'

Macron is expected to address the nation around 1800 GMT, presidential sources revealed, in a speech that government spokesperson Olivier Veran claimed on Saturday would be in the spirit of "pacification".

But the leader of the powerful CGT union Sophie Binet said in an interview with regional newspapers on Sunday that Macron was "on his way to becoming the president of chaos."

"He is opening the way to the National Rally" party of Le Pen, who was shown in one poll as the victor if the 2022 presidential election was re-run at the present time, Binet said.

In an editorial, Le Monde daily noted that Le Pen was the only French politician whose popularity has been notably boosted by the crisis, while trust in the country's democratic institutions has fallen.

"The cost of the pensions reform appears to be exorbitant," it said.

The crisis also comes at a time of increasing challenges on the international stage for Macron, who faced accusations of acting friendly to China on a visit to Beijing last week.

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'Macron no longer has authority'

Macron, 45, came to power in 2017 promising reform in France and a fresh new politics. But opponents accuse him of following an increasingly reclusive and anti-democratic behavior.

"Emmanuel Macron no longer has authority ... so suddenly he is becoming brutal and authoritarian," hard-left deputy Clementine Autain told French TV on Sunday.

Le Pen said Macron had three choices to end a crisis "which he created himself" -- a referendum on the changes, legislative elections, or resignation.

But Prime Minister Elisabeth Borne vowed Saturday that the government would press ahead with more reforms now that the pensions overhaul was passed.

"We are determined to accelerate" the pace of reforms, she told the national council of Macron's Renaissance party.

Binet and other union bosses have called for a "popular and historic tidal wave" of people on the streets to oppose the reforms on May 1.

As a prelude to the May 1 protests, railway unions are calling for a day of "railway anger" on April 20.

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